n 1  :  any of several plants formerly used in the treatment of respiratory disorders : esp  :  a European herb (Pulmonaria officinalis) of the borage family (Boraginaceae) with rough hairy leaves and bluish flowers  2  :  a widely distributed lichen (Lobaria pulmonaria) formerly used in the treatment of bronchitis and now to some extent in perfumes and in tanning extracts .
 
   
 
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